日本ベル投資研究所 has compiled developments in the spread of AI innovation and movements in Japanese equities. The report also covers developments including Kioxia Holdings overtaking Toyota Motor in market capitalization in June, alongside investment risks in the AI era.
In Japan's equity market, Kioxia Holdings' market capitalization reached ¥44 trillion in June, overtaking Toyota Motor to become the largest company. Kioxia is seeking a turnaround under Bain Capital, which is promoting its semiconductor memory business, while the market capitalization of SB Group and the rise in Tokyo Electron's share price also stood out.
Kioxia suffered losses during the memory downturn in 2023. Its market capitalization was ¥860 billion when it was listed in December 2024, but expanded rapidly to ¥44 trillion over the following 1.5 years. The arrival of the AI boom became apparent in 2025 and is viewed as having translated into earnings.
The market capitalization of South Korean semiconductor memory company SK hynix was ¥160 trillion, while Samsung Electronics' was ¥200 trillion, underscoring the substantial gap with Japanese companies. SK hynix is ahead in HBM technology and is pursuing the world's leading share of the HBM market for AI data centers.
Cybersecurity vulnerabilities have been identified as an AI risk, and advances in AI may affect defense and economic security. Alongside developments at NVIDIA and OpenAI, the report presents the view that dual-use challenges should be examined.